Fig. 36 (after Sordelli)
Head-Shields.—Rostral deeper than broad, its width two-thirds to seven-eighths its depth, extending to the upper edge of the snout. As a rule, with the exception of the large supraocular, the upper surface of the head is covered with small, subimbricate scales, which are smooth, very rarely feebly keeled, between the eyes and on the snout; however, an enlarged frontal shield, or even a frontal and a pair of parietals, are sometimes present, though rarely so large as in a typical V. berus; when present, the frontal is separated from the supraocular by one or two series of scales; when the frontal is absent, four to seven series of scales separate the supraoculars. Upper surface of snout usually bordered by eight or nine small shields—viz., two or three apicals, in contact with the tip of the rostral and raised to form the turned-up nose, and, on each side, two canthals and the upper preocular, which separates the supraocular from the canthals, or three canthals; sometimes, however, the border is formed by six or seven small shields, the second canthal being in contact with the supraocular, as in V. berus. Supraocular usually with very convex outer border, not extending posteriorly beyond the vertical of the eye. Eight to thirteen scales round the eye, usually ten to twelve; one or two vertical series of scales separate the preoculars from the nasal, which is single or divided, and often rather deeply hollowed out. As a rule two series of scales (very rarely three) separate the eye from the labials; sometimes, however, there is but one scale between the eye and the fourth labial, the second series being incomplete. Upper labials nine to thirteen, usually nine to eleven, fourth and fifth, rarely fourth to sixth or fifth and sixth, below the eye. Temporal scales smooth or feebly keeled. Four (rarely five) lower labials in contact with the single pair of chin-shields.
VIPERA ASPIS
After Calmette
VIPERA LATASTII
Scales in twenty-one or twenty-three (rarely nineteen or twenty-five) rows, with two apical pits, strongly keeled, those of the outer row more or less distinctly keeled, rarely perfectly smooth. Ventral shields 134 to 158 (usually 143 to 153) in males, 141 to 169 (usually 145 to 157) in females; anal entire; subcaudals 32 to 49 (usually 37 to 45) in males, 30 to 43 (usually 32 to 38) in females; the terminal caudal shield is sometimes shorter and less spine-like than in V. berus, quite obtuse in some specimens.
Coloration.—Grey, greyish-brown, brown, reddish-brown, coppery red, or orange, is the ground colour in individuals from the same district; in this respect sexual differences are less marked than in the preceding species, red or copper-coloured specimens being found in both sexes, and silvery white specimens do not seem ever to occur. In rare cases markings are entirely absent. In specimens from the greater part of France, Italy, and the Southern Tyrol (see [Plate XIII].), the dark brown or black markings on the body are mostly in the form of narrow cross-bars, continuous across the back or broken on the vertebral line and often alternating with each other and with similar bars on the sides, thus producing a pattern not unlike that frequently found in Tropidonotus natrix; a narrow dark line running straight or zigzag along the spine may connect these cross-bars, and in rare cases it is so broad as to produce a zigzag band similar to that of V. berus. In specimens from South-Western France and the Pyrenees, rarely in some from other parts of France and Italy, there is a broad dark grey or brown vertebral band between two series of black or blackish-brown spots, opposite to each other or alternating; this band may be straight or wavy, sometimes forming a regular zigzag; there is another series of blackish spots or short bars lower down on the side, alternating with those of the dorsal series.
The upper surface of the head may be devoid of any markings, or bear merely the two oblique dark streaks forming the branches of a Λ; or a dark cross-bar may be present on the snout, followed or not by smaller spots or a pair of oblique streaks on the occiput; the Λ on the back of the head may be united with the first cross-bar on the nape, and enclose a cordiform figure of the lighter ground colour. A light line sometimes borders the upper edge of the snout and the outer edge of the supraocular shield. A blackish band or a mere line extends obliquely from the eye to the first lateral spot; below this the upper lip is whitish, yellowish, or pinkish, with or without dark vertical bars on the sutures between the labial shields. The iris is golden or coppery red.